Cellular digital packet data
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| Mobile communication standards |
| GSM / UMTS (3GPP) Family |
| GSM (2G) |
| UMTS (3G) |
| UMTS Rev. 8 (Pre-4G) |
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| cdmaOne / CDMA2000 (3GPP2) Family |
| cdmaOne (2G) |
| CDMA2000 (3G) |
| UMB (Pre-4G) |
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| AMPS Family |
| AMPS (1G) |
| D-AMPS (2G) |
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| Other Technologies |
| 0G |
| 1G |
| 2G |
| Pre-4G |
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| Channel Access Methods |
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| Frequency bands |
Cellular Digital Packet Data (CDPD) uses unused bandwidth normally used by AMPS mobile phones between 800 and 900 MHz to transfer data. Speeds up to 19.2 kbit/s are possible.
Developed in the early 1990s, CDPD was large on the horizon as a future technology. However, it had difficulty competing against existing slower but less expensive Mobitex and DataTac systems, and never quite gained widespread acceptance before newer, faster standards such as GPRS became dominant.
CDPD had very limited consumer offerings. AT&T Wireless first offered the technology in the United States under the PocketNet brand. It was one of the first consumer offerings of wireless web service. A company named Omnisky provided service for Palm V devices. Cingular Wireless later offered CDPD under the Wireless Internet brand (not to be confused with Wireless Internet Express, their brand for GPRS/EDGE data). PocketNet was generally considered a failure with competition from 2G services such as Sprint's Wireless Web. After the four phones AT&T Wireless had offered to the public (two from Panasonic, one from Mitsubishi and the Ericsson R289LX), AT&T Wireless eventually refused to activate the devices.
Despite its limited success as a consumer offering, CDPD was adopted in a number of enterprise and government networks. It was particularly popular as a first-generation wireless data solution for telemetry devices (machine to machine communications) and for public safety mobile data terminals.
In 2004, major carriers in the United States announced plans to shut down CDPD service. In July 2005, the AT&T Wireless and Cingular Wireless CDPD networks were shut down.
